3, 20-dihaloacetoxy pregnanes and process for the production thereof



United States Patent 3,258,457 3,20-DIHALOACETOXY PREGNANES AND PROC- ESS FOR THE PRODUCTION THEREOF Fred A. Kine], Atherton, Calif., assignor to Syntex Corporation, Panama, Panama, a corporation of Panama No Drawing. Filed Oct. 4, 1963, Ser. No. 313,770 20 Claims. (Cl. 260239.55)

This invention relates to novel cyclopentanopolyhydrophenanthrene derivatives and to processes for their preparation.

More particularly, this invention relates to. novel 21- dihaloacetate esters of 21-hydroxypregnane derivatives such as those compounds represented by the general formula:

In the above formula R represents hydrogen, p-hydroxyl or a keto group; R represents hydrogen or a hydroxyl group; R represents hydrogen, a-methyl, fi-methyl, a-hydroxyl or an a-acyloxy group containing less than 12 carbon atoms; R and R taken together can also represent the grouping:

wherein R and R can each represent hydrogen, a lower alkyl (including cycloalkyl) group containing up to 10 carbon atoms, such as methyl, ethyl, propyl, isobutyl, cyclobutyl, cyclopentyl, cyclohexyl, cyclodecyl, and the like, a monocyclic aryl hydrocarbon (including alkaryl and aralkyl) group containing up to 10 carbon atoms, such as phenyl, benzyl, dimethylbenzyl, methylethylbenzyl, and the like, or a monocyclic heterocyclic group, such as furfuryl, thiophenyl, and the like; X represents hydrogen, fluorine or chlorine, with X being hydrogen when R is hydrogen; X represents hydrogen, methyl, fluorine or chlorine, all of which can be in either the uor the B-configuration when there is a saturated linkage between the carbon atoms and the 6- and 7-positions; Z represents either a double bond or a saturated linkage between the carbon atoms at the land 2-posi tiions; Z represents either a double bond or a saturated linkage between the carbon atoms at the 6- and 7-positions, and P and Q each represent either fluorine or chlorine.

The conventional acyloxy groups which can be present at the l6a-position of the novel 21-dihaloacetoxy pregnane derivatives of the present invention are derived from hydrocarbon carboxylic acids containing less than 12 carbon atoms. These acids can be saturated or unsaturated, straight, branched, cyclic or cyclicaliphatic, and can also be either unsubstituted or subsituted, e.g., with hydroxyl groups, alkoxy groups containing up to carbon atoms, acyloxy groups containing up to 12 carbon atoms, a nitro group, an amino group, a halogen atom, and the like. Included among such ester groups are the acetate, t-butylacetate, trimethylacetate, aminoacetate, phenoxyacetate, propionate, cyclopentylpropionate, ,B-chloropropionate,

ice

CHzOH wherein R, R R X, X Z and Z have the same meaning as set forth hereinabove for Formula I, with a dihaloacetic acid, a dihaloacetyl halide or a dihaloacetic anhydride wherein the halogen atoms attached to the acetyl moiety are either fluorine or chlorine.

The present invention is based on the surprising and unexpected discovery that esterification of the 2l-hydroxyl group in these known 2l-hydroxy corticoids with the above-described dihaloacetyl groups potentiates their corticoid activity, thus permitting them to be used therapeutically at lower dosage levels at which the corresponding conventional 2.1-esters, e.g., the acetates, are no longer sufliciently active.

The esterification reaction, as periodically indicated, can be carried out using either a free dihaloacetic acid, i.e. dichloroacetic acid, difiuoroacetic acid or fluorochloroacetic acid, a corresponding acid halide, preferably the chloride, e.g., dichloroacetyl chloride and the like, or a dihaloacetic anhydride, e.g., dichloroacetic anhydride and the like. Several esterification procedures, all of which have previously been used in conventionally esterifying steroidal hydroxyl groups, can be followed. First of all, esterification can be carried out in an inert organic solvent, preferably pyridine, collidine, lutidine, and thelike, as well as mixtures thereof with each other or with one or more other inert organic solvents, such as benzene, toluene, xylene, and the like, at a temperature ranging from room temperature (about 25 C.) or lower to about C. for from about 30 minutes to about 15 hours or longer, using either a dihaloacetyl halide or a dihaloacetic anhydride. Secondly, esterification can also be accomplished in an inert organic solvent, such as benzene, toluene, xylene and the like, as well as mixtures thereof, in the absence of pyridine and the like, by using a free dihaloacetic acid of the anhydride thereof either alone or in the presence of a strongly acidic esterification catalyst, such as benzenesulfonic acid, p-toluenesulfonic acid, and the like. This latter esterification procedure will generally be carried out at reflux temperature for periods of time ranging up to 15 hours or more, with provision being made for the continual removal of water formed during the re action,

In working up the reaction mixtures obtained using the first of the above-described procedures, the reaction mixture is usually washed first with dilute aqueous hydrochloric acid and then with an aqueous solution of sodium carbonate, while in working up the reaction mixtures 9a fluoro A -pregnadiene-11B,l6a,l7a,21-tetrol-3,20-

dione,

90c fluoro-16a,l7isopropylidenedioxy-A -pregnadiene- =1 1;i,2-l-diol-3,20-dione,

60,9oc difiuoro l6a-methyl-A -pregnadiene-1 1/5317 u,2l-

triol-3,20-dione,

6a,9oc difiuoro-A pregnadiene l1B,16a,17a,21-tetrol- 3,20-dione,

60,9oc difiuoro l6a,l7u isopropylidenedioxy A pregnadiene-l 1,8,2 1-diol-3,20-dione,

60!,906 difiuoro A pregnadiene-l lB,16ot,l7a,2l-tetrol- 3,20-dione-l6a,l7a acetal,

6u,9a difiuoro A -pregnadiene 11B,16a,-17a,2l-tetrol- 3,20-dione methyl ethyl ketal,

60,9cc difiuoro A pregnadiene-l1,B,l6a,l7a,2l-tetro1- 3,20-dione diethyl ketal,

604,911 difiuoro A pregnadiene-ll,8,l6a,l7a,2l-tetrol- 3,20-dione methyl isobntyl ketal,

6a,9a difiuoro A pregnadiene-l lfl,16t .,17a,2l-tetrol- 3,20-dione cyclohexylidene ketal,

6a,9e difiuoro A pregnadiene-llfi,l6a,17u,2l-tetrol- 3,20-dione methyl phenyl ketal,

6oz chloro 9oz fluoro-A -pregnadiene-l15,16a,17a,21-

tetrol-3,2(l-dione,

6oz chloro 9a fluoro-16a,17a-isopropylidenedioxy-A pregnadiene-l1B,2l-dio]-3,20-dione,

A -pregnatriene-1113,l7a,2l-triol-3,20-dione,

A -pregnatriene-l 1B,16oc,l7ot,21-t6tfOl-3 ,20-dione,

the like,

as Well as, in the case of those 2l-hydroxpregnanes containing hydroxyl groups at the *16OL-pOSltlOn, the conventional acylates thereof, e.g., the acetates, propionates,

enanthates, and the like.

In order that those skilled'in the art can more fully understand the present invention, the following examples are set forth. These examples are given solely for the purpose of illustration, and should not be considered as and expressing limitations unless so set forth in the appended claims. Example I A mixture of 1 gram of A -pregnene-17a,21-diol-3,ll, ZO-trione, 2 grams of dichloroacetyl chloride and 4 cc. of pyridine was charged to a suitable reaction vessel and reacted overnight at room temperature (about 25 C.). Next, the reaction mixture was poured into ice water and the precipitate formed thereby was filtered, washed with water and dried. Crystallization of the dried precipitate from acetone-hexane resulted in a substantially quantitative yield of A -pregnene-l7a,2l-diol-3,l1,20-trione 2l-dichloroaoetate.

Examples II and III The procedure of Example I was repeated in every detail in each of these examples with one exception, namely, dichloroacetyl chloride was replaced by di fluoroacetyl chloride and fluorochloroacetyl chloride, respectively. Substantially quantitative yields of the ZI-difiuor-oacetate and ZI-fluorochloroacetate of A -pregnene-l7a,2l-diol-3,11,20- trione, respectively, were obtained.

Examples IV-VI By using A -pre'gnene-11B,17oc,21-triol-3,2O-dione in place of A -pregnene-l7a,2l-diol-3,11,20-trione in the procedure of Examples I, II and III, the 2l-dichloroacetate, 2ll-difiuoroacetate and 21 fluorochloroacetate, respectively, were obtained in substantially quantitative yields.

Examples VII-X V The procedure of Example I was again repeated in every detail in each of these examples with the following exceptions. First of all, A -pre-gnene-l7a,2l-diol-3,11,20-trione was replaced by ZO-trione; 6a,9u difiuoro 1601,170: isopropylidenedioxy-A -pregnadiene-l1fl,2.1-diol-3,20-dione; 6a fluoro 16oz methyl A pregnadiene-ll;8,l7a,2l-

triol-3,2l0-dione and 9a fluoro l6B-rnethyl-A -pregnadiene-l l5,l7a,2ll-triol- 3,20-dione, respectively.

In addition, dichloroacetyl chloride was replaced in Examples VII-IX by difluoroacetyl chloride, fluorochloroacetyl chloride and dichloroacetic anhydride, respectively. This resulted in substantially quantitative yields of 60a methyl A pregnene-l7a,2l-diol-3,l1,20-trione 21- difiuoroacetate;

60c methyl M-pregnene-l1,8,l7ot,21-triol-3,20-dione 21- fluorochloroacetate and the 2l-dichloroacetates of 1606,1706 isopropylidenedioxy A pregnen2l-ol-3,1l,20-

trione;

60c chloro 9a fluoro-A -pregnadiene-l7a,2l1-diol-3,1 1,

20-trione;

60,90t difiuoro 16ix,17u isopropylidenedioxy-A -pregnadiene-l 15,2l-diol-3 ,20-dione;

60c fluoro 16cc methyl A -pregnadiene-11/3,l7a,2.1-

triol-3,20-dione and 9a fiuoro 16,8 methyl 13 -pregnadiene-1l;3,17a,2l-

triol-3,20-dione respectively.

It will be obvious to those skilled in the art that other changes and variations can be made in carrying out the present invention without departing from the spirit and scope thereof as defined in the appended claims.

I claim:

1. A 3,20-diketo-Zl-dihaloacetoxy-A -pregnene wherein the halogen atoms in said dihaloacetoxy group are selected from the group consisting of fluorine and chlorine.

2. A compound according to claim 1 wherein the dihaloacetoxy is dichloroacetoxy.

3. A compound according to claim 1 wherein the dihaloacetoxy is difiuoroacetoxy.

4. A compound according to claim 1 wherein the dihaloacetoxy is fluorochloroacetoxy.

5. A compound represented by the general formula:

wherein R is selected from the group consisting of hydrogen, ,B-hydroxyl and a keto group; R is selected from the group consisting of hydrogen and hydroxyl; R is selected from the group consisting of hydrogen, a-methyl, ,8- methyl, a-hydroxyl and an acyloxy group containing less than 12 carbon atoms; R and R taken together represent the grouping:

wherein R and R are each selected from the group consisting of hydrogen, a lower alkyl group, an aryl hydrocarbon group and a heterocyclic group; X is selected from the group consisting of hydrogen, fluorine and chlorine, with X being hydrogen when R is hydrogen; X is selected from the group consisting of hydrogen, methyl, fluorine and chlorine; Z and Z are selected from the group consisting of a double bond and a saturated linkage between the carbon atoms at the 1- and 2- and 6- and 7-positions, respectively, and P and Q are each selected from the group consisting of fluorine and chlorine.

6. A pregnene-17u,2l-diol-3,l1,20-trione-21-dichloroacetate.

7. A pregnene-17u,21-diol-3,11,20-trione-21-difluoroacetate.

8. A pregnene 17a,21-diol-3,l1,20-trione-21-fluorochloroacetate.

9. A pregnene 11,8,170:,21-triol-3,2O-dione-21-dichloroacetate.

10. A pregnene 11/3,l7oc,21 triol-3,2=O-dione-21-difluoroacetate.

11. A pregnene-l1,8,l7a,21-triol-3,20-dione-21-fluorochloroacetate.

12. 60c methyl A pregnene-17a,21-di0l-3,l1,20-trione-Zl-difluoroacetate.

13. c methyl A pregnene 11B,17a,21-triol-3,20- -dione-2lfluorochloroacetate.

14. 9oz fluoro A pregnene-17u,21-diol-3,11,20-trione-Zl-dichloroacetate.

15. 9a fluoro A pre-gnene-l1B,17a,21-trio1-3,20-dione-Zl-dichloroacetate.

16. 1604,17oc isopropylidenedioxy A pregnen-Zbol- 3,1 1,20-trione-21-dichloroacetate.

17. 60c chloro c fluoro A -pregnadiene-17a,2ldiol-3,1 1,20-trione-21-dichl0roacetate.

18. 604,900 difluoro ,17OL-lSOPIOPYlldEHCdlOXY-A pregnadiene-l 15,21 -diol-3 ,20-dione-2 l-dichloroacetate.

19. 60c fluoro 16oz methyl-A -pregnadiene-11,8,17a, 21 -triol-3,20-dione-2l -dichloro acetate.

20. 90c fluoro 16B methyl-A -pregnadiene-l15,17a, 21-triol-3,2'0-dione-21-dichloroacetate.

References Cited by the Examiner UNITED STATES PATENTS 2/ 1959 Korman 2J60397.45 2/1959 Hogg et a1 2/60-397.45 

1. A 3,20-DIKETO-21-DIHALOCAETOXY-$4-PREGNENE WHEREIN THE HALOGEN ATOMS IN SAID DIHALOACETOXY GROUP ARE SELECTED FROM THE GROUP CONSISTING OF FLUORINE AND CHLORINE. 